I figured out how to buy lettuce in bulk and make it last up to 3 weeks - that's my longest record so far. I wash the lettuce and pull the leaves off the base. Then I tear it into salad size pieces and place them on a paper towels (usually 3 of the select a size towels). Once I've filled the paper towels with a layer of salad, I then roll the lettuce up to absorb the moisture into the paper towels.
When I've finished washing and tearing up all my lettuce, I get a gallon size plastic bag (sounds counter-intuitive to recycling but you can reuse the bag until it wears out or you rip it in your forays for lettuce). I then place a section of the paper towel I used to dry the lettuce which is now moist into the bottom of the bag, layer the lettuces I tore up on top - I usually do Romaine, Green and Red lettuce together, layer another piece of the paper towel and more lettuce until the bag is full. Seal the bag squeezing out most of the extra air. The gas released off the lettuce is absorbed into the paper towels and the lettuce will last for 2 - 3 weeks (you'll see red marks from the gas on your towels instead of the lettuce leaves and stems). When you finish with a bag, you can rinse it out with hot water, let it dry and save it for the next round of lettuce. The paper towels that don't get used in the bags are then used to clean the kitchen counters and floors that night so I get double use out of them.

When I bring my radishes home I separate them and cut off all the green leaves so they don't get all slimy.I store them in a paper towel so they last longer.Also they are all cleaned up for a quick snack.I have learned over the years that plastic is the killer of fresh veggies.

As soon as I get a head of lettuce home, I take it out of the plastic wrapping so it doesn't get slimy and spoil. I rip it in half and wash it and put it in my salad spinner and get all the excess water off and out of it, and keep it stored in my spinner.. It lasts a really long time, and it stays crispy and yummy///When I get my green onions home I take the rubber bands off of them, and take that first layer off, and store them in a paper towel loose. it keeps them from drying out on top and getting slimy where the rubber band was//With cilantro, I take off the twist tie rinse it, get all the excess water off and store in a mug of water on the top of my fridge.Make sure the leaves do not get into the water.